Dapr

The Distributed Application Runtime (Dapr) is a set of incrementally adoptable features that simplify the authoring of distributed, microservice-based applications.

Dapr provides capabilities for enabling application intercommunication through messaging via pub/sub or reliable and secure service-to-service calls.

Dapr is often used to implement the [[sidecar-pattern]]. The main application communicates with the sidecar via [[gRPC]] or HTTP;

Dapr exposes several APIs:

• Service-to-service invocation: Discover services and perform reliable, direct service-to-service calls with automatic [[mTLS]] authentication and encryption.
• State management: Provides state management capabilities for transactions and CRUD operations.
• Pub/sub: Allows publisher and subscriber container apps to intercommunicate via an intermediary message broker.
• Bindings: Trigger your applications based on events
• Actors: Dapr actors are message-driven, single-threaded, units of work designed to quickly scale. For example, in burst-heavy workload situations.
• Observability: Send tracing information to an Application Insights backend.
• Secrets: Access secrets from your application code or reference secure values in your Dapr components.

Dapr uses a modular design where functionality is delivered as a component.